Telescopic or retractable seating systems, commonly referred to as bleachers, provide a degree of flexibility when employed in multi-purpose environments such as gymnasia. During practice periods, there is little need for ample seating as there are typically few spectators. However, during sporting competitions, assemblies, or concerts, accommodation for large groups is necessary. The provision of one discrete chair per person would require excessive manpower and time and storage of such chairs would be complex and space-intensive. Telescopic or retractable bleacher systems can be retracted when seating is not required and extended when an audience is expected.
Preferably, such seating systems are provided with aisle rails to assist individuals in maintaining their balance as they mount or descend the seating system aisles. In fact, certain localities have codified requirements for the provision of aisle rails.
Advances have been made in the mechanisms utilized to reconfigure such bleacher systems, including powered drives for automatic or semi-automatic operation. This further reduces the manpower requirement for reconfiguring the seating systems. However, advances in aisle rail storage and deployment have lagged the advances in seating system manipulation. Thus, the prior art includes aisle rails that must be manually turned or folded from a use position to a stored position, that must be manually removed and stored separately from the seating system, or that must be accommodated in a deployed position when the seating system is retracted, such as by providing a cut-out or other discontinuity in the seating system, by limiting the degree of retraction of the seating system in a closed position, or both. Such prior art systems fail to minimize the manpower required to retract and deploy seating systems with aisle handrails, fail to maximize the usable space in an area in which the seating systems are located due to protruding rails in the closed position, or both.
One approach to addressing these problems is to provide a pivotable handrail in conjunction with a bleacher system. In one embodiment, the handrail comprises an elongated gripping portion at an upper end thereof and a post therebeneath. The post is provided with an outwardly extending cam at a lower end thereof. A cylindrical retaining member surrounds the lower extent of the post and the cam is received in a helical cam slot in the retaining member. The retaining member is affixed to a front or “nose” portion of a deck of the bleacher system. A ramp is disposed on a step below the deck on which the retaining member is mounted. When the bleacher system is extended, the ramp upper surface comes into contact with the post lower extent. As the ramp continues outward with the bleacher system, the post is driven upwards and the cam follows the helical cam slot, thereby rotating the handrail 90 degrees from a closed position, in which the gripping portion is perpendicular to the respective bleacher system aisle, to an open position, in which the gripping portion is aligned with the respective aisle. During bleacher system retraction, the post lower extent moves out of engagement with the ramp and the step upon which it is mounted moves back and under the deck front portion on which the retaining member is mounted. The post thus lowers and, as the cam follows the helical cam slot, rotates 90 degrees from the open position to the closed position.
However, the frictional engagement of multiple aisle rails may increase the force required to reconfigure the bleacher system from either the retracted position to the open position or vice versa. This is particularly true in environments where particulates may be carried onto the bleacher system steps. Such particulates may include sand, dirt, and salt used for de-icing applications.
There thus exists a need for alternative systems and methods for enabling the automatic deployment and retraction of aisle rails in bleacher systems.